Nonfoaming compositions and methods of making same



Patented Feb. 12, 1946 NONFOAMING COMPOSITIONS AND METHODSOF MAKING SAME Hillside, and John 0. Zrmmer, Union, N. J assignors to Standard Oil Development Company, a corporation of Dela- Garland H. B. Davis,

ware

No Drawing.

Application December 31, 1943, Serial No. 516,546

15 Claims. (01. 252-3a4) engines, particularly the heavy duty type of oils.

Many internal combustion engines employ both pressure and splash systems of lubrication, whereas other motors use only one of the systems. In either case the formation of foam On top of the oil during the operation of the motor leads to serious consequences due to lack of lubrication. This is particularly so in pressure lubrieating systems employing the so-called dry sump operation where the oil returning from the engine parts is picked up by a scavening pump and returned to the lubricant reservoir.

.Since the scavenging pump normally has a capacity of several times the volume of the oil returning from the engine, a large amount of air is pumped along with the lubricant and as a result foam tends to build up in the oil reservoir to a point where some oil may be lost through the breather pipe or to a point where the pressure pump delivers foam instead of oil to the various moving parts of the engine, with a resultant lack of lubrication. Many heavy duty lubricating oils for gasoline and Diesel engines contain dissolved therein from 0.5-5% of various metallo-organic additives, such as metal phenates, phenol sulfides, carboxylates, sulfonates, alcoholates, metal salts of esters of phosphorus and thio phosphorus acids, etc., which as oil soluble detergents act to maintain bearings and the internal surfaces of the engines free of ummy or. varnish like deposits. Oils containing additives of the above type are especially prone to foam under many conditions; The addition to oils of certain non-metallic agents, such as phosphatides, organic esters, fatty compounds, thickeners, etc., also promotes foaming on occasion.

In the case of gear lubricants, such as those designed for the lubrication of automobilerear ends and transmissions, when such lubricants show a marked tendency toform foam during grease;

use the foam entraps the lubricant to such an extent that the oil level will fall below the gear train. These oils usually owe their abilit to withstand high unit loads to the presence of additives containing sulfur, chlorine or phosphorus or to the presence of lead soaps.- Hydraulic and shock absorber oils likewise need protection against foaming.

Another instance where a serious foaming problem exists is in the production of metal sulfonatesfrom petroleum oil sulfonic acids, and particularly the preferentially oil-soluble sulfonic acids. In general the petroleum oil sulfonic acids are produced when mineral oil or a fraction thereof is treated with concentrated sulfuric acid. The oil-soluble sulfonic acids are recovered as metal sulfonates by first removing the acid sludge, converting the sulfonic acids to sulfonates by neutralization with alkali and removing the resulting metal sulfonates from the oil by washing the oil with aqueous alcohol. The alcohol is then recovered by distillation, leaving as a residue metal sulfonates mixed with an aqueous solution of mineral salts. Near the end of the alcohol distillation step large volumes of foam are produced and space in the apparatus must be provided for accommodating this foam so as to prevent it going over into the condenser.

There are many uses for sulfonates which require a metal sulfonate other than an alkali metal sulfonate. These metal sulfonates, as for example the alkaline earth-metal sulfonates, are made by a process of double decomposition between alkali metal sulfonates and an aqueous solution of an alkaline earth metal salt. After the reaction is completed the material is concentrated by boiling ofi the water. Here again foaming occurs which at times reaches such proportions as to require an evaporator 10 times as large in volume as the volume of the metal sulfonates being concentrated. Another process which is conducive to the formation of foam is that of making greases such as ordinary cup The ordinary procedure for making greases is to melt soap stock in lubricatingoil and then react the soap stock with an alkali or alkaline material added in the form of an aqueous solution or suspension after which most, if not all, of the water is boiled off. During the boiling off of the water the hot grease is usually stirred vigorously and large quantities'of foam are produced. still another instance'in which the presence of foam attains troublesome amounts is in the production of additives for lubricating compositions. For example, in the production of metal phenates and phenol sulfldes in oil solution, large volumes of foam are produced during the neutralization step in which the water of reaction must be driven off. It has been found that in processes where foaming occurs, vessels at least 2 and 3 times and often times the size, measured by volume of the materal being processed, must be provided in order to secure expeditious results. It is therefore apparent that if foaming could be eliminated in these various processes, appreciable economies in time. labor and materials could be effected.

The principal object of the present invention is to provide lubricating compositions which will not froth or foam during use. Another object is to dispense with the troublesome foaming accompanying ebullition in the dehydration of oil solutions and mixtures. These and other objects will be apparent to those skilled in the art upon reading the following description.

It has now been found that certain highly fluorinated organic compounds particularly those derived from aliphatic, aromatic or naphthene hydrocarbons in which the major proportion of the hydrogen has been replaced with fluorine, will, when added to spumiferous compositions, reduce to negligible proportions the tendency of such compositions to form foam when stripped by means of heat and will also when present in small amounts materially depress foaming due to aeration or deaeration in oleaginous compositions of matter, such as engine oils (both compounded and uncompounded), hydraulic fluids, shock absorber oils", cutting oils, extreme pressure lubricants, process oils, saturating compositions, asphaltic oils and various other related compositions, as well as oil concentrates containing from 5 to 50% or more of additives for use in preparing the above products. The fluorinated hydrocarbons may be added to the oleaginous compositions at any stage of their manufacture or may be incorporatedwith one or more of these additives prior to theaddition of the additive or mixture of additives to the oily material as for instance the fiuorinated hydrocarbon may be included with the metal soaps of the petroleum oil sulfonic acids, such as the calcium soaps; the metal soaps oforganic thiophosphoric acid, such as the zinc soaps; metal phenates, metal alkylated phenates, metal phenol sulfides, metal alkylated phenol sulfides, like metal tertiary octyl phenol sulfide and metal alkylated phenol sulfldes reacted with P285, where the metal is a polyvalentmetal such as barium; and the like. The fluorinated compounds may also contain chlorine, bromine or iodine, oxygen, nitrogen, phosphorus, sulfur or metal derivatives of functional groups in the molecule.

, from various sources including petroleum frac- The highly fiuorinated compounds contemplated within the scope of the present invention are known and their properties and preparation have been described by both Bochemuller and at about 215-240 Simmons. For the purpose of the present invention it is preferred to use those highly fluorinated compounds which have boiling points above 85 C. at atmospheric pressure and viscosities between 302000 S. U. S. at 210 compounds having from heptafluoropcntane (C5H5F7), octafluorpentane (CsHzF'a), dodecafluoropentane (C5F'12) and simiiar derivatives of such hydrocarbons as pentadecane, eicosane, and cyclic, isomeric, and normal aliphatics of 5 to 50 carbon atoms, in which at least half of the hydrogen atoms are replaced by fluorine atoms. Preferably the number of F. This range includes tions ranging from gasoline to heavy lubricating oils, or waxes and petrolatums. These fluorinated hydrocarbons will contain from about 60 to about fluorine, from about 20 to about 37% carbon and from zero to about 3% hydrogen. It is preferred to use fluorinated compounds in which substantially all of the hydrogen has been replaced In practicing the to the dehydration of spumiferous compositions the fluoro-organic compounds may be added to the spumiferous composition to be dehydrated either before or after the composition has been charged to an evaporating vessel, in an amount equivalent to from 1-50 grams per thousand square'inches of evaporating surface. Since many evaporation vessels have or provide irregular evaporating surfaces, the amount of fluoro-organic compound added to the spumiferous compositions can be calculated on the basis of weight per cent of the charge to the evaporator. Expressed in this manner it requires from 0.000140% by weight (based on the total charge) to suppress the formation of foam during subsequent evaporation in order that the dehydration can be conducted rapidly without interference from foam. Such processes can be run either by a batch method or continuously. When it is desired to suppress foaming in compositions such as lubricants, hydraulic media, and the like the fiuoro=organic compound is added to such compositions in an amount from .0001-10% by weight. The fluoroorganic compounds are substantially insoluble,

and although having a greater specific gravity than many common fluids, it is believed that the fluorine compounds possess the characteristic of concentrating at the interface between the liquid phase and the gaseous foam phase, thereby break- Example 1 A process for converting sodium sulfonate to the calcium sulfonate involves emulsifying an oil solution of the sodium sulfonate with a dilute aqueous calcium chloride solution and heating F. to drive off the water. In reacting 200 grams of 30% sodium sulfonate in oil, the total volume of reactants does not eX- ceed 350 ml., but it is necessary to employ a 2 liter beaker and slow heating to avoid foaming over of the product. When, however, 0.1% of a highly fluorinated hydrocarbon containing 26.30% fluorine and having a viscosity of 67 S. U. S. at 210 F. is employed, it is possible to complete the heating operation in of the time and to use a 600 ml. beaker.

Example 2 816 pounds of 30% sulfonate in oil and 629 present invention as applied carbon, 0.09% hydrogen and 71.30% of pounds of an 11% calcium chloride solution in water and 1 pound of a highly fluorinated hydrocarbon containing 26.5'0% carbon, .09% hydrogen and 71.30% of fluorine and having a viscosity of 67 S. U. S. at 210 F. are placed in a kettle and heated to 240 F. for 1% hours to react the sodium sulfonate with the calcium chloride and to drive off the water by evaporation. Without the fluorine compound only about 325 pounds of reactants can be charged to the kettle and it would require about 12 hours to complete the reaction and drive off all the Water.

Example 3 .measure of the foaming tendency of the oil.

Various highly fluorinated hydrocarbons were then tested for defoaming characteristics with the following results:

Percent volume increase S. A. E.-30 Heavy duty motor oil 22 +0.1% 9 +0.1 +0.01% 2 +0.1% 0 +0.01% 0 +01% 6 A highly fiuorinated aliphatic hydrocarbon containing 26.30% carbon, .09% hydrogen and 73.30% of fluorine and having a viscosityof 67 S. U. S. at 210 F.

A highly fluorinated aliphatic hydrocarbon containing 24.24% carbon, 0.12% hydrogen and 67.03% fluorine.

A highly fluorinated aliphatic hydrocarbon containing 24.25% carbon, 0.05% hydrogen, 73.59% fluorine.

4A highly fluorinated aliphatic hydrocarbon containing 24.66% carbon, 0.18% hydrogen and 68.07% fluorine.

It will be seen that the fluorinated hydrocarbon compounds of the present invention were highly eflective in reducing the foaming tendencies of the heavy duty lubricant.

What is claimed is:

1. In a method for dehydrating spumiferous materials in which the material is heated to the point of ebulliency, the step of adding to the material to be dehydrated a small amount of a fluoro-organic compound having from -50 carbon atoms to the molecule and in which the fluorine represents at least 50% of replaced hydrogen.

2. An improved method for thermally dehydrating spumiferous materials which comprises adding to the materialto be dehydrated from about .0001 to about 10% by weight of a fluoroorganic compound having from 5-50 carbon atoms to the molecule and in which the number of fluorine atoms in the molecule exceeds the number of carbon atoms in the molecule by at least 1.

3. An improved method for thermally dehydrating spumiferous materials which comprises adding to the material to be dehydrated from .0001-10% by weight of a highly fluorinated aliphatic hydrocarbon containing about 26% carbon, about .1% hydrogen and about 73% of fluorine and having a viscosity of 6'7 8. U. S. at 210 F.,

and heating to drive off the water. v

4. An improved method for thermally dehydrating spumiferous material which comprises adding to the material to be dehydrated from .0001-10% by weight of a highly fluorinated allphatic hydrocarbon containing from 60-80% of fluorine, 20-37% carbon and 0-3% hydrogen, and heating to drive off water.

5. An improved method for producing grease compositions comprising dissolving soap stock in mineral lubricating oil, reacting the soap stock with an aqueous solution of alkaline material, adding from .0001-10% by weight of a fluoroorganic compound chosen from the group consisting of aliphatic and cycle aliphatic fluoroorganic compounds having from 5-50 carbon atoms to the molecule and in which the number of fluorine atoms in the molecule exceeds the number of carbon atoms in the molecule by at least 1, heating to drive off at least a portion of the water and to react the ingredients to form the grease.

6. In an improved method of introducing a metal ion into the hydroxyl radical attached to an aromatic nucleus, water, which is subsequently removed by vaporization, being present during the reaction, the improvement which consists in adding to the reaction product prior to thermal dehydration from .0001-10% by weight of a fluoro-organic compound chosen from the group consisting of aliphatic and cycle aliphatic fluoroorganic compounds having from 5-50 carbon atoms to the molecule and in which the number of fluorine atoms in the molecule exceeds the number of carbon atoms in the molecule by at least 1, and heating to drive off the water.

7. An improved method for producing grease compositions comprising dissolving soap stock in mineral lubricating oil, reacting the soap stock with an aqueous-solution of alkaline material, adding from .0001-10% by weight of a fluoroorganic aliphatic hydrocarbon containing about 26% carbon, about .1% hydrogen and about 73% of fluorine and having a viscosity of 67 S. U. S. at 2l0 F. and heating to drive off at least a portion of the water.

8. An improved method for producing grease compositions comprising dissolving soap stock in mineral lubricating oil, reacting the soap stock with an aqueous solution of alkaline material, adding from .0001-10% by weight of a fluoroorganic aliphatic hydrocarbon containing from 60-80% fluorine, 20-37% carbon, and 0-3% hydrogen, and heating to drive off at least a portion of the water.

9. An improved method for producing metal sulfonates comprising reacting a, basic material selected from the class consisting of alkali and alkaline earth compounds with a solution of sulfonic acids in a vehicle selected from the group consisting of oil and alcohol, adding to the resultant sulfonate-containing composition, prior to thermal dehydration from .0001-10% by weight of a fluoro-organic aliphatic hydrocarbon containing about 26% carbon, about .1% hydrogen and about 73% of fluorin and having a viscosity of 67 S. U. S. at 210 F. and heating to drive off at least a portion of the water.

10. An improved method for producing metal sulfonates comprising reacting a basic material selected from the class consisting of alkali and alkaline earth compounds with a solution of sulionic acids in a vehicle selected from the group consisting of oil, alcohol and aqueous alcohol, adding to the resultant sulfonate-containing composition, prior to thermal dehydration from .0001-10% by weight ofa fluoro-organic aliphatic hydrocarbon containing from 60-80% fluorine, 20-37%carbon, and 0-3% hydrogen, and heating to drive 01f at least a portion of the water.

11. In an improved method or introducing a metal ion into the hydroxyl radical attached to an aromatic nucleus, water which is subsequently removed by boiling, being present during the reaction, the improvement which consists in add- .ing to the reaction product prior to thermal dehydration from '.0001-10% by weight 01 a micro-.-

removed by boiling, being present during the' reaction, the improvement which consists in adding to the reaction product prior to thermalwlehydration from .0001-10% by weight-of a fluoroorganic aliphatic hydrocarbon containing 60-80% fluorine, 20-37% carbon and 0-3% hydrogen, and heating to drive off at least a, portion of the water.

13. An improved method for producing metal suii'onates comprising reacting a basic material selected from the class consisting of alkali and alkaline earth compounds with a solution of suli'onic acidsi'n a vehicle selected from the group;

consisting 01,011 and alcohol, addingto the resultant sulfonate-containing composition, prior to thermal dehydration, 0.1% by weight of a fluoro-organic aliphatic hydrocarbon containing about 26% carbon, about .1% hydrogen and about 73% of fluorine and having a viscosity of 67 S. U. S. at 210 F. and. heating to drive oil at least a portion of the water. l

14. An improved method for producing metal sulfonates comprising reacting a basic material selected from the class consisting of alkali and alkaline earth compounds with a solution of sulfonic acids in a vehicle selected from the group consisting oi oil, alcohol and aqueous alcohol, adding to the resultant sulfonate-containing composition, prior to thermal dehydration, 0.1% by weight oi a fluoro-organic aliphatic hydrocarbomcontaining 60-80% fluorine, 20-30% carbon and 0-3% hydrogen, and heating to drive 011 at least a portion of the water.

- 15. In av method tor dehyd ating spumiierous materials in which the material is heated to the point of ebulliency, the step of adding to the material to be dehydrated a small amount of fluoro-organic compound having from 5-50 carbon atoms to the molecule and in which substantially all of the hydrogen has been fluorine.

GARLAND H. B. DAVIS.

JOHN 0,

replaced by 

